Note: VH400 model is compatible with HOBO U12 loggers only by using the specially designes SSE Electronics. It is also directly compatible with the analog channels of the HOBO U30 and H22 loggers and stations, and the GP2 Data Logger from Delta-T.

The VH400 has a narrow sensing range, and only senses in the immediate proximity, and so is insensitive to differences in the volume of the medium being measured.

If the probe is going to be buried or if the probe is going to be used to measure pots of differing volumes then the VH400 should be used.

Use the VH400 soil moisture sensors in soils where the soil will have higher water saturation.Use the VH400 where you need an absolute moisture measurement that is independent of volume, as in the case of measuring moisture in potted plants.